Heat exchanger transfer tubes

ABSTRACT

A transfer tube for a thermal transfer device can include at least one wall having an inner surface and an outer surface, where the inner surface forms a cavity, where the at least one wall further has a first end and a second end. The first end can be configured to couple to a terminus of a heat exchanger of the thermal transfer device. The second end can be configured to couple to a collector box of the thermal transfer device. At least a portion of the at least one wall can be disposed in a vestibule of the thermal transfer device. The cavity can be configured to simultaneously receive a first fluid that flows from the first end to the second end and a second fluid that flows from the second end to the first end.

TECHNICAL FIELD

Embodiments described herein relate generally to heat exchangers, andmore particularly to transfer tubes for heat exchangers.

BACKGROUND

Heat exchangers, boilers, combustion chambers, water heaters, and othersimilar devices (generally called heat exchangers or vessels herein)control or alter thermal properties of one or more fluids. In somecases, tubes (also called heat exchanger tubes or HX tubes) disposedwithin these devices are used to transfer a fluid through a volume ofspace, thereby altering the thermal properties of the fluid. Thetemperature of the fluid can increase or decrease, depending on how theheat exchanger is configured.

SUMMARY

In general, in one aspect, the disclosure relates to a transfer tube fora thermal transfer device. The transfer tube can include at least onewall having an inner surface and an outer surface, where the innersurface forms a cavity, where the at least one wall further has a firstend and a second end. The first end can be configured to couple to aterminus of a heat exchanger of the thermal transfer device. The secondend can be configured to couple to a collector box of the thermaltransfer device. At least a portion of the at least one wall can bedisposed in a vestibule of the thermal transfer device. The cavity canbe configured to receive a first fluid that flows from the first end tothe second end. The cavity can further be configured to receive a secondfluid that flows from the second end to the first end. At least one wallcan be configured to receive the first fluid and the second fluidsimultaneously.

In another aspect, the disclosure can generally relate to a thermaltransfer device that includes a main chamber and a vestibule disposedadjacent to the main chamber. The main chamber can include a pluralityof heat exchanger tubes through which a first fluid flows, where eachheat exchanger tube comprises an entrance and an exit. The main chambercan also include a blower assembly that blows a second fluid across theplurality of heat exchanger tubes. The vestibule can include an inducerand a burner assembly coupled to the entrance of the plurality of heatexchanger tubes. The vestibule can also include a collector box thatreceives the first fluid and removes condensation from the first fluid.The vestibule can further include a first transfer tube having at leastone first wall having a first inner surface and a first outer surface,where the first inner surface forms a first cavity, where the at leastone first wall farther has a first end and a second end. The first endof the first transfer tube can be coupled to the exit of at least one ofthe plurality of heat exchanger tubes positioned in the main chamber.The second end of the first transfer tube can be coupled to thecollector box in the vestibule. The transfer tube can provide the firstfluid to the collector box. The transfer tube can transport thecondensation from the collector box to a drain proximate to the exit ofthe at least one of the plurality of heat exchanger tubes.

These and other aspects, objects, features, and embodiments will beapparent from the following description and the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings illustrate only example embodiments of transfer tubes forheat exchangers of climate control units and are therefore not to beconsidered limiting in scope, as transfer tubes for heat exchangers mayadmit to other equally effective embodiments. The elements and featuresshown in the drawings are not necessarily to scale, emphasis insteadbeing placed upon clearly illustrating the principles of the exampleembodiments. Additionally, certain dimensions or positions may beexaggerated to help visually convey such principles. In the drawings,reference numerals designate like or corresponding, but not necessarilyidentical, elements.

FIGS. 1A through 1D show various views of a climate control unitcurrently used in the art and with which example embodiments can beused.

FIGS. 2A through 2C show a non-compliant design of a climate controlunit with ultra-low NO_(x) capability.

FIGS. 3A through 3C show various views of a climate control unit inaccordance with certain example embodiments.

FIG. 4 shows a transfer tube in accordance with certain exampleembodiments.

FIG. 5 shows another transfer tube in accordance with certain exampleembodiments.

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS

The example embodiments discussed herein are directed to systems,methods, and devices for transfer tubes for heat exchangers of climatecontrol devices (e.g., air conditioning units, furnaces) or other typesof thermal transfer devices. Example embodiments can be directed to anyof a number of thermal transfer devices, including but not limited tofurnaces, boilers, condensing boilers, traditional heat exchangers, andwater beaters. Further, one or more of any number of fluids can flowthrough example transfer tubes. Examples of such fluids can include, butare not limited to, water, deionized water, steam, glycol, anddielectric fluids.

Example embodiments can be pre-fabricated or specifically generated(e.g., by shaping a malleable body) for a particular heat exchangerand/or environment. In other words, heat exchangers can be specificallydesigned to include example transfer tubes and/or existing heatexchangers can be retrofitted to accommodate example transfer tubes.

The transfer tubes (or components thereof) described herein can be madeof one or more of a number of suitable materials and/or can beconfigured in any of a number of ways to allow the transfer tubes (ordevices (e.g., furnace, boiler, heat exchanger) in which the transfertubes are disposed) to meet certain standards and/or regulations whilealso maintaining reliability of the transfer tubes, regardless of theone or more conditions under which the transfer tubes can be exposed.Examples of such materials can include, but are not limited to,aluminum, stainless steel, ceramic, fiberglass, glass, plastic, andrubber.

As discussed above, heat exchangers that include example transfer tubescan be subject to complying with one or more of a number of standards,codes, regulations, and/or other requirements established and maintainedby one or more entities. Examples of such entities can include, but arenot limited to, the American Society of Mechanical Engineers (ASME), theTubular Exchanger Manufacturers Association (TEMA), the American Societyof Heating, Refrigeration and Air Conditioning Engineers (ASHRAE),Underwriters' Laboratories (UL), the National Electric Code (NEC), theInstitute of Electrical and Electronics Engineers (IEEE), and theNational Fire Protection Association (NFPA). Example transfer tubesallow a heat exchanger to continue complying with such standards, codes,regulations, and/or other requirements. In other words, example transfertubes, when used in a heat exchanger, do not compromise compliance ofthe heat exchanger with any applicable codes and/or standards.

Any example transfer tubes, or portions thereof, described herein can bemade from a single piece (e.g., as from a mold, injection mold, diecast, 3-D printing process, extrusion process, stamping process,crimping process, and/or other prototype methods). In addition, or inthe alternative, example transfer tubes (or portions thereof) can bemade from multiple pieces that are mechanically coupled to each other.In such a case, the multiple pieces can be mechanically coupled to eachother using one or more of a number of coupling methods, including butnot limited to epoxy, welding, fastening devices, compression fittings,mating threads, and slotted fittings. One or more pieces that aremechanically coupled to each other can be coupled to each other in oneor more of a number of ways, including but not limited to fixedly,hingedly, removeably, slidably, and threadably.

As described herein, a user can be any person that interacts withtransfer tubes or heat exchangers in general. Examples of a user mayinclude, but are not limited to, an engineer, a maintenance technician,a mechanic, an employee, a visitor, an operator, a consultant, acontractor, and a manufacturer's representative. Example transfer tubesare coupled to one or more components of a heat exchanger using one ormore of a number of coupling features. As used herein, a “couplingfeature” can couple, secure fasten, abut and/or perform other functionsaside from merely coupling.

A coupling feature as described herein can allow one or more sections ofa transfer tube to become coupled, directly or indirectly, to anotherportion (also called sections herein) of the transfer tube and/or a heatexchanger. A coupling feature can include, but is not limited to, asnap, a clamp, a portion of a hinge, an aperture, a recessed area, aprotrusion, a slot, a spring clip, a tab, a detent, a compressionfitting, swage or expansion process, and mating threads. One portion ofan example transfer tube can be coupled to a component (e.g., a header,a collector box) of a heat exchanger and/or another portion of thetransfer tube by the direct use of one or more coupling features.

In addition, or in the alternative, a portion of an example transfertube can be coupled to another component of a heat exchanger and/oranother portion of the transfer tube using one or more independentdevices that interact with one or more coupling features disposed on acomponent of the transfer tube. Examples of such devices can include,but are not limited to, a swage, an expansion, a weld, a pin, a hinge, afastening device (e.g., a bolt, a screw, a rivet), epoxy, adhesive, anda spring. One coupling feature described herein can be the same as, ordifferent than, one or more other coupling features described herein. Acomplementary coupling feature as described herein can be a couplingfeature that mechanically couples, directly or indirectly, with anothercoupling feature.

Any component described in one or more figures herein can apply to anyother figures having the same label. In other words, the description forany component of a figure can be considered substantially the same asthe corresponding component described with respect to another figure.The numbering scheme for the components in the figures herein parallelthe numbering scheme for corresponding components described in anotherfigure in that each component is a three digit number and correspondingcomponents have identical last two digits. For any figure shown anddescribed herein, one or more of the components may be omitted, added,repeated, and/or substituted. Accordingly, embodiments shown in aparticular figure should not be considered limited to the specificarrangements of components shown in such figure.

Example embodiments of transfer tubes for heat exchangers will bedescribed more fully hereinafter with reference to the accompanyingdrawings, in which example embodiments of transfer tubes for heatexchangers are shown. Transfer tubes for heat exchangers may, however,be embodied in many different forms and should not be construed aslimited to the example embodiments set forth herein. Rather, theseexample embodiments are provided so that this disclosure will bethorough and complete, and will fully convey the scope of transfer tubesfor heat exchangers to those of ordinary skill in the art. Like, but notnecessarily the same, elements (also sometimes called components) in thevarious figures are denoted by like reference numerals for consistency.

Terms such as “first,” “second,” “top,” “bottom,” “left,” “right,”“end,” “back,” “front,” “side”, “length,” “width,” “inner,” “outer,”“above”, “lower”, and “upper” are used merely to distinguish onecomponent (or part of a component or state of a component) from another.Such terms are not meant to denote a preference or a particularorientation. Such terms are not meant to limit embodiments of transfertubes for heat exchangers. In the following detailed description of theexample embodiments, numerous specific details are set forth in order toprovide a more thorough understanding of the invention. However, it willbe apparent to one of ordinary skill in the art that the invention maybe practiced without these specific details. In other instances,well-known features have not been described in detail to avoidunnecessarily complicating the description.

FIGS. 1A through 1D show various views of a climate control unit 199currently used in the art and with which example embodiments can beused. Specifically, FIG. 1A shows a semi-cross-sectional perspectiveview of the climate control unit 199 FIG. 1B shows a cross-sectionalfront view of the climate control unit 199. FIG. 1C shows across-sectional side view of the climate control unit 199. FIG. 1D showsa detailed perspective view of a portion of the primary tubes 110 of theclimate control unit 199. In this case, the climate control unit 199 iscapable of providing heating and air conditioning services.

Referring to FIGS. 1A through 1D, the climate control unit 199 in thiscase is a furnace. The climate control unit 199 includes one or more ofany number of components. For example, in this case, the climate controlunit 199 of FIGS. 1A through 1D includes at least one inner wall 196that divides the interior of the climate control unit 199 into a mainchamber 198 and a vestibule 197. The main chamber 198 of the climatecontrol unit 199 is a space in which heat is transferred from one fluidto another. The main chamber 198 of the climate control unit 199 ofFIGS. 1A through 1D includes a blower assembly 155, a shelf 150 on whichthe blower assembly 155 is disposed, and multiple heat exchanger tubes120.

The vestibule 197 of the climate control unit 199 of FIGS. 1A through 1Dincludes a burner assembly 110 (which includes one or more burners 115),a collector box 130, a fuel line 131, an inducer 140, an exhaust vent145, a barrier 135, and a controller 105. In this case, the barrier 135separates the controller 105 from the rest of the equipment in thevestibule 197. The vestibule 197 is separated from the air streamgenerated by the blower assembly 155. The blower assembly 155 pushes airfrom above the blower shelf 150 to the portion of the main chamber 198below the blower shelf 150 so that the air pushes across the heatexchanger tubes 120. The portion of the main chamber 198 above theblower shelf 150 is under negative pressure, and the portion of the mainchamber 198 below the blower shelf 150 is under positive pressure. Thevestibule 197 is under negative pressure relative to inside the heatexchanger tubes 120, inside the collector box 130, and the inducer 140.In other words, the inducer 140 provides a negative pressure in relationto all of the other components of the climate control unit 199.

When in heating mode, the process of combusting a first fluid (e.g.,natural gas) to heat another fluid (e.g., air) in the climate controlunit 199 of FIGS. 1A through 1D begins at the burner assembly 110 in thevestibule 197, where the first fluid interacts with a flame generated byeach of the burners 115. For example, a mixture of a gaseous fuel (e.g.,natural gas, propane, butane) and air can be used to transfer heat to afluid (e.g., air, water), and the resulting heated fluid (e.g., air,water, steam) can be used for some other process or purpose. The gaseousfuel can be brought to the burner assembly 110 by the fuel line 131. Inthe context of a furnace, the climate control unit 199 is used to heatair, which is then circulated through a building (e.g., a house, anoffice space). In some cases, the fuel can be premixed with some othercomponent, such as air. For example, the fuel/air mixture can beintroduced into the burner assembly 110.

Once inside the burner assembly 110, each of the burners 115 can apply aflame to the fuel/air mixture to ignite and raise the temperature of thefuel/air mixture, resulting in combustion and burning of the fuel/airmixture. In this case, as shown in FIG. 1D, there are four burners 115,and each burner 115 of the burner assembly 110 feeds the heated fuel/airmixture into an end of a heat exchanger tube 120. From there, theresulting hot gases (byproducts of the combustion of the fuel/airmixture) can be directed into the entrance (the end coupled to theburners 115) of the various heat exchanger tubes 120 in the main chamber198. These heat exchanger tubes 120 are placed below the blower shelf150 and often are laid out in a non-linear, sloped arrangement tomaximize the amount of surface area exposed in the main chamber 198.

After flowing through the heat exchanger tubes 120, the remainder of thefuel/air mixture leaves the exit (the end coupled to the collector box130 or tubing thereto) of the heat exchanger tubes 120 and travels tothe collector box 110 in the vestibule 197. The collector box 130 isdesigned to capture additional condensation that builds in the fuel/airmixture. The collector box 130 can have any of a number of componentsand/or configurations to cover the exiting end of the heat exchangertubes 120 to collect flue product and transfer it from the heatexchanger tubes 120 to the inducer 140 while maintaining a discreteoperating pressure required for combustion and flow.

After the collector box 130, the hot gases then continue on to theinducer 140 in the vestibule 197 and leave the climate control unit 199through the exhaust vent 145. The inducer 140 typically includes a fandriven by a motor. When the fan of the inducer 140 operates, air movesSince the inducer 140 is positioned adjacent to the exhaust vent 145 inFIGS. 1A through 1D, the arrangement of the climate control unit 199 inthis case is sometimes referred to as a pull-through or induced-airfurnace. This is because the inducer 140 pulls or induces the fuel/airmixture from the burner assembly 110, through the heat exchanger tubes120, and through the collector box 130 before being vented through theexhaust vent 145.

When this process involving the fuel/air mixture is occurring, anotherfluid (e.g., air) is brought into the main chamber 198 of the climatecontrol unit 199. Once inside the main chamber 198, the fluid comes intocontact with the outer surfaces of the heat exchanger tubes 120. In manycases, the heat exchanger tubes 120 are made of a thermally conductivematerial. In this way, when the hot gases (from the combustion process)travel through the heat exchanger tubes 120, some of the heat from thefuel is transferred to the walls of the heat exchanger tubes 120.Further, as the fluid comes into contact with the outer surface of thewalls of the heat exchanger tubes 120, some of the heat captured by thewalls of the heat exchanger tubes 120 from the heated fuel istransferred to the fluid in the main chamber 198. The blower assembly155 is used to pass the fluid in the main chamber 198 over the heatexchanger tubes 120 and send the heated fluid out of the climate controlunit 199. The heated fluid can then be used for one or more otherprocesses, such as space heating, or in the case of a water heater, hotwater for use in a shower, a clothes washing machine, and/or adishwashing machine.

In air conditioning mode, the process is modified Specifically, thecombustion process does not occur because the climate control unit 199is providing air conditioning rather than heating. The air conditioningsection of the climate control unit 199 is located upstream of theblower assembly 155. The cool air from the evaporator 119 of the airconditioning section is blown across the exterior of the heat exchangertubes 120 by the blower assembly 155. The result is that condensationforms inside of the heat exchanger tubes 120, particularly when theambient environment in which the climate control unit 199 is placed isvery hot and/or humid (e.g., in the summertime). Oftentimes, the climatecontrol unit 199 operates in air conditioning mode for months at a time.By, contrast, when the climate control unit 199 operates as a heater (asopposed to an air conditioner), heated fluid moves through the heatexchanger tubes 120, preventing any condensation from accumulatinginside the heat exchanger tubes 120.

This condensation accumulates inside the heat exchanger tubes 120. Asthe heat exchanger tubes 120 are often arranged with sloping runs, thecondensate that accumulates inside the heat exchanger tubes 120 isgravity-fed to a collection area adjacent to a lower end of the heatexchanger tubes 120. The burners 115 of the burner assembly 110 in thiscase are exposed (open) to allow some of the condensation (water) todrain from within the heat exchanger tubes 120 when the ambientenvironment in which the climate control unit 199 is placed is hot,thereby generating a large amount of condensation when the heatexchanger is not in operation because the climate control unit 199 isoperating in air conditioning (condensing) mode.

In some cases, as when a climate control unit (e.g., climate controlunit 199) has ultra-low NO_(x) (ULN) emissions, the climate control unit(or components thereof) is configured in such a way that allows for thecomplete and efficient burning of a fuel (e.g., natural gas) beforereaching the heat exchanger tubes (e.g., heat exchanger tubes 120) whilealso maintaining spacing requirements with respect to the height of theblower shelf (e.g., blower shelf 150). Unfortunately, options are verylimited in this regard without the use of example transfer tubes, asdiscussed below.

For example, FIGS. 2A through 2C show an example of a climate controlunit 289 that is configured with a sealed premix burner system for ULNemissions but that fails to meet spacing requirements and/or otherapplicable standards. Specifically, FIG. 2A shows a top-front-sideperspective view of a portion of an ULN climate control unit 289 thatdoes not include an example transfer tube and fails to meet designspecifications. FIG. 2B shows a top-side-rear view of the ULN climatecontrol unit 289. FIG. 2C shows a cross-sectional side view of the ULNclimate control unit 289. Referring to FIGS. 1A through 2C, the climatecontrol unit 289 of FIG. 2 has the same components described above forthe climate control unit 199 of FIGS. 1A through 1D. For example, theclimate control unit 289 of FIGS. 2A through 2C includes an inducer 240,a collector box 230, and a burner assembly 210 disposed in a vestibule297, where these components correspond to the inducer 140, the collectorbox 130, and the burner assembly 110 disposed in the vestibule 197 ofthe climate control unit 199 of FIGS. 1A through 1D.

In this case, however, the premix burner assembly 210 of the climatecontrol unit 289 of FIGS. 2A through 2C is configured differently thanthe the burner assembly 110 of the climate control unit 199 of FIGS. 1Athrough ID. Specifically, rather than being open to allow for drainageof condensation that builds in the heat exchanger tubes 220, as with theburner assembly 110 of FIGS. 1A through 1D, the burner assembly 210 ofthe climate control unit 289 is sealed. This sealed configuration of theburner assembly 210 is effective for controlling the amount of air thatmixes with the fuel when the fuel is burned. Also, the fuel iscompletely burned by the burner assembly 210 of FIGS. 2A through 2Cbefore reaching the heat exchanger tubes 220 of the climate control unit289. This process optimizes the air/fuel mixture and reduces emissionssuch as nitrogen oxide, carbon monoxide, and carbon dioxide from flowingthrough the heat exchanger tubes 120 and being expelled via the inducer140 into the ambient environment.

A drawback to this arrangement of FIGS. 2A through 2C, however, is thatthe burner assembly 210 is relatively bulkier than an open burnerassembly (e.g., burner assembly 110) and must be placed higher up in thevestibule 297. One option to account for this is to place the inducer240 and collector box 230 underneath the burner assembly 210. However,when this occurs, the heat exchanger tubes 220 in the main chamber 298are positioned, at least in part, above the blower shelf 250. As aresult, the blower shelf 250 (and so also the blower) must also beelevated, which increases the overall height of the climate control unit289. When this occurs, the climate control unit 289 cannot be, used in anumber of applications and situations because of height restrictions. Inthis way, an arrangement of components in the main chamber 298 and thevestibule 297 must be engineered without raising the height of theblower shelf 250. As shown in FIGS. 3A through 3C, example transfertubes allow for this arrangement to be possible.

FIGS. 3A through 3C show various views of climate control unit 300 inaccordance with certain example embodiments. Specifically, FIG. 3A showsa top-front-side perspective view of the climate control unit 300. FIG.3B shows a cross-sectional front view of the climate control unit 300.FIG. 3C shows a cross-sectional side view of the climate control unit300.

Referring to FIGS. 1A through 3C, the climate control unit 300 of FIGS.3A through 3C has a number of components that are substantially similarto the components of the climate control unit 199 of FIGS. 1A through1D. For example, the climate control unit 300 of FIGS. 3A through 3Cincludes at least one inner wall 396 that divides the interior of theclimate control unit 300 into a main chamber 398 and a vestibule 397.The main chamber 398 of the climate control unit 300 is a space in whichheat is transferred from one fluid to another. The main chamber 398 ofthe climate control unit 300 of FIGS. 3A through 3C includes a blowerassembly 355, a shelf 350 on which the blower assembly 355 is disposed,and multiple heat exchanger tubes 320.

The vestibule 397 of the climate control unit 300 of FIGS. 3A through 3Cincludes a burner assembly 310, a collector box 330, an inducer 340, anexhaust vent 345, a barrier 335, and a controller 305. These componentsare substantially the same as the corresponding components of theclimate control unit 199 of FIGS. 1A through 1D discussed above. Forexample, the barrier 335 separates the controller 305 from the rest ofthe equipment in the vestibule 397. In this case, however, the burnerassembly 310 is sealed, as in FIG. 2 , rather than open as in FIGS. 1Athrough ID. As discussed above, this configuration of having a sealedburner assembly 210 is commonly used for ULN burners of the burnerassembly 310. As a result, the components of the vestibule 397 and themain chamber 398 must be rearranged with respect to the arrangement ofFIGS. 1A through 10D.

While the inducer 340 and collector box 330 of the climate control unit100 remain positioned above the burner assembly 310, the burner assembly310 has been moved vertically upward relative to what is shown in FIGS.1A through 1D. As a result, the heated fuel/air mixture leaving theburners of the burner assembly 310 travel down the heat exchanger tubes320 rather than up the heat exchanger tubes 320, as what is shown inFIGS. 1A through 1D. Condensation that accumulates inside the heatexchanger tubes 320 is gravity-fed to a collector within the headerplate 321 at the distal end of the heat exchanger tubes 320. Given thelimited amount of space in terms of the footprint of the climate controlunit 300, this configuration of components shown in FIGS. 3A through 3Ccan pose design problems and/or performance issues (e.g., unwantedpressure drop).

To resolve most, if not all, of these issues, one or more exampletransfer tubes 370 can be added to the climate control unit 300 of FIGS.3A through 3C. In this case, a single example transfer tube 370 isdisposed, at least in part, in the vestibule 397. The transfer tube 370has one end that is connected (coupled) to the header plate 321 disposedat the return (distal) end of the heat exchanger tubes 320 and anotherend that is connected (coupled) to the collector box 330. In this way,by using example transfer tubes 370, the process flow of the fuel/airmixture of the climate control unit 300 of FIGS. 3A through 3C can bethe same as the process flow of the fuel/air mixture of the climatecontrol unit 199 of FIGS. 1A through 1D, even though the components ofthe climate control unit 300 are rearranged to allow for ULNcapabilities.

The header plate 321 is used to cover the lower collector box 131, whichis used to channel the fuel/air mixture flowing through multiple heatexchanger tubes 320 into one end of the example transfer tube 370. Theheader plate 321 and the lower collector box 331 may be unique to thedesign of the climate control unit 300. Alternatively, the header plate321 and the lower collector box 331 can be a standard configuration forthe climate control unit 300. In some cases, the header plate 321 andthe lower collector box 331 can include one or more features (e.g., acollector, a drain) that allows accumulated water received from the heatexchanger tubes 320 (and, in some cases, also from the transfer tube370) to drain out of the climate control unit 300 when condensationforms inside of the heat exchanger tubes 320 when the climate controlunit 300 is in air conditioning mode and is located in a hot and/orhumid environment, such as what is typically encountered duringsummertime operation.

Also, as discussed above, the collector box 330 can be configured toseparate condensation from the fuel-air mixture. In any case, some orall of the condensation accumulated by the collector box 330 can rundown the transfer tube 370 to the header plate 321 if the header plate321 is equipped with a drain or other similar feature to allow thecondensation to leave the climate control unit 300. As the climatecontrol unit 300 can be running continuously, the example transfer tube370 can receive the flow of the fuel/air mixture in one direction andthe flow of condensation in the opposite direction simultaneously.

As shown in FIGS. 4 and S below, example transfer tubes described hereincan have any of a number of shapes, sizes, and/or configurations. Forexample, a transfer tube (e.g., transfer tube 370) can have an overalllength (e.g., two inches, four inches), have at least one curvedsection, and have at least one optional linear section. Since the flueproduct carried inside the transfer tube 370 is under negative pressurein relation to the vestibule 397 in which the transfer tube 370 isdisposed, if a portion of the transfer tube 370 located in the vestibule397 is punctured, develops a hole, or is otherwise compromised, then anyflue product from the combustion of the fuel-air mixture will not leak(or have only minimal leaking). This means that the example transfertube 370 has a built-in fail-safe feature.

While only a single transfer tube 370 is shown in this example, aclimate control unit 300 can have multiple transfer tubes 370, if aclimate control unit 300 has multiple transfer tubes 370, then onetransfer tube 370 can have the same, or different, configurations (e.g.,shape, material, size, number of branches, number of linear sections,number of curved sections, curvature of curved sections) relative to theother transfer tubes 370.

As stated above, example transfer tubes described herein can have any ofa number of shapes, sizes, and/or configurations needed or desired tomaintain the preferred system pressure required. FIG. 4 shows a transfertube 470 in accordance with certain example embodiments. FIG. 5 showsanother transfer tube 570 in accordance with certain exampleembodiments. Referring to FIGS. 1A through 5 , the transfer tube 470 ofFIG. 4 is non-planar. The bottom end 472 of the transfer tube 470 has alinear section 473, which then transitions to a curved section 474(which in this case forms an approximately 90° bend), which thentransitions to another linear section 473, which then transitions to acurved section 474 (which in this case forms an approximately 90° bendin a different plane), which then transitions to another linear section473, which then transitions to a curved section 474 (which in this caseforms an approximately 90° bend in a different plane), which thenfinishes with another linear section 473 at the top end 471.

The transfer tube 570 of FIG. 5 forms a planar U-shape Specifically, thebottom end 572 of the transfer tube 570 begins with a linear section573, which then transitions to a curved section 574 (which in this caseforms an approximately 90° bend), which then transitions to anotherlinear section 573, which then transitions to another curved section 574(which in this case forms an approximately 90° bend in the same plane),which then finishes with another linear section 573 at the top end 571.Each linear section (e.g., linear section 573) of a transfer tube (e.g.,transfer tube 570) can have any length, thickness, squareness of edges,and/or other characteristics. Similarly, each curved section (e.g.,curved section 574) of a transfer tube (e.g., transfer tube 570) canhave any length, thickness, number of bends (e.g., one, three), radiusof a bend, squareness of edges, and/or other characteristics.

In certain example embodiments, a transfer tube can have other sectionsnot shown in FIGS. 3A through 5 . For example, part of a transfer tubecan include a junction (e.g., a T-junction, a Y-junction, a crossjunction) that leads to multiple branches. In such a case, a transfertube can have three or more ends that can couple to different componentsof a heat exchanger of a climate control unit. For instance, a climatecontrol unit can have multiple collector boxes (e.g., collector box 330,collector box 332) and/or multiple header plates 321. In such a case, asingle transfer tube with 3 or more ends can be used. Alternatively,multiple transfer tubes (e.g., each with two ends, each with four ends)can be used in a single climate control unit. In such a case, onetransfer tube can have the same, or different, shape, size, and/orconfiguration relative to the shape, size, and/or configuration of oneor more of the other transfer tubes of the climate control unit.

The cross-sectional shape of an example transfer tube described hereincan have one or more of any of a number of shapes along the length ofthe transfer tube Examples of such shapes can include, but are notlimited to, a circle (as in the examples shown above with respect toFIGS. 3A through 5 ), square, octagonal, triangular, oval, and random.The cross-sectional area of an example transfer tube can besubstantially uniform or variable along its length. Each end (e g,bottom end 472, top end 571) of an example transfer tube can include oneor more coupling features (e.g., mating threads).

An example transfer tube described herein can be used in climate controlunits having certain configurations that accumulate condensation withoutan effective manner in draining such condensation. An example of such aclimate control unit is a furnace that has ULN capability using a sealedburner assembly. Example transfer tubes can be used to move a combustionproduct (e.g., a fuel/air mixture) from below the burner assembly of theheat exchanger to a collector box located above the burner assembly.When an example transfer tube is located inside the vestibule of theclimate control unit, the transfer tube can have inherent fail-safefunctionality in the event that the transfer tube is compromised. Theexample transfer tubes help to drain condensation that builds in airconditioning mode when the cold air is passed over a hot heat exchangertubes in summer months or when heating the fuel/air mixture in a heatexchange process of the heat exchanger.

By carefully engineering the placement and the various characteristicsof each transfer tube, the transfer tube can provide a number ofbenefits, including but not limited to higher efficiency, moreconsistent pressure, lower costs, and less waste. Example HX tubes canallow a climate control unit to comply with any applicable standardsand/or regulations. Example embodiments can be mass produced or made asa custom order. Example embodiments can be used in newly-manufacturedclimate control units or in retrofitting existing climate control units.

Accordingly, many modifications and other embodiments set forth hereinwill come to mind to one skilled in the art to which example transfertubes pertain having the benefit of the teachings presented in theforegoing descriptions and the associated drawings. Therefore, it is tobe understood that example transfer tubes are not to be limited to thespecific embodiments disclosed and that modifications and otherembodiments are intended to be included within the scope of thisapplication. Although specific terms are employed herein, they are usedin a generic and descriptive sense only and not for purposes oflimitation.

1. (canceled)
 2. A thermal transfer device comprising: a main chambercomprising: a plurality of heat exchanger tubes through which a firstfluid flows, wherein each heat exchanger tube comprises an entrance andan exit; and a blower assembly that blows a second fluid across theplurality of heat exchanger tubes; and a vestibule disposed adjacent tothe main chamber, wherein the vestibule comprises: an inducer; a burnerassembly coupled to an upper side of the plurality of heat exchangertubes; a collector box configured to receive the first fluid and removecondensation from the first fluid; and a transfer tube having a firstend and a second end, wherein the first end is coupled to the exit of atleast one of the plurality of heat exchanger tubes, and the second endis coupled to the collector box; wherein the first fluid is configuredto flow through the plurality of heat exchanger tubes in a downwardsdirection and then in upwards directions above the burner assembly. 3.The thermal transfer device of claim 2, wherein the transfer tubeprovides the first fluid to the collector box, and wherein the transfertube transports the condensation from the collector box to a drain. 4.The thermal transfer device of claim 3, wherein the drain is proximateto the exit of the at least one of the plurality of heat exchangertubes.
 5. The thermal transfer device of claim 2, wherein the thermaltransfer device comprises a single transfer tube.
 6. The thermaltransfer device of claim 2, wherein the vestibule further comprises alower collector box and a header plate configured to cover the lowercollector box.
 7. The thermal transfer device of claim 6, wherein thelower collector box further comprises a drain configured to allowaccumulated water received from the plurality of heat exchanger tubes tobe drained when condensation forms inside of the plurality of heatexchanger tubes.
 8. The thermal transfer device of claim 2, wherein thecollector box is disposed above the burner assembly.
 9. The thermaltransfer device of claim 8, wherein the inducer is disposed above theburner assembly.
 10. The thermal transfer device of claim 2, wherein theburner assembly is a sealed burner assembly.
 11. The thermal transferdevice of claim 2, wherein the transfer tube has a negative pressurerelative to a pressure of the main chamber and the vestibule.
 12. Athermal transfer device comprising: a plurality of heat exchanger tubesthrough which a first fluid flows, wherein each heat exchanger tubecomprises an entrance and an exit; a blower assembly that blows a secondfluid across the plurality of heat exchanger tubes; a vestibule disposedadjacent to the main chamber, wherein the vestibule comprises: aninducer; a burner assembly coupled to an upper side of the plurality ofheat exchanger tubes; a collector box configured to receive the firstfluid and remove condensation from the first fluid; and a transfer tubehaving a first end and a second end, wherein the first end is coupled tothe exit of at least one of the plurality of heat exchanger tubes, andthe second end is coupled to the collector box; wherein the first fluidis configured to flow through the plurality of heat exchanger tubes in adownwards direction and then in upwards directions above the burnerassembly.
 13. The thermal transfer device of claim 12, wherein thetransfer tube provides the first fluid to the collector box, and whereinthe transfer tube transports the condensation from the collector box toa drain.
 14. The thermal transfer device of claim 13, wherein the drainis proximate to the exit of the at least one of the plurality of heatexchanger tubes.
 15. The thermal transfer device of claim 12, whereinthe thermal transfer device comprises a single transfer tube.
 16. Thethermal transfer device of claim 12, further comprising a lowercollector box and a header plate configured to cover the lower collectorbox.
 17. The thermal transfer device of claim 16, wherein the lowercollector box further comprises a drain configured to allow accumulatedwater received from the plurality of heat exchanger tubes to be drainedwhen condensation forms inside of the plurality of heat exchanger tubes.18. The thermal transfer device of claim 12, wherein the collector boxis disposed above the burner assembly.
 19. The thermal transfer deviceof claim 18, wherein the inducer is disposed above the burner assembly.20. The thermal transfer device of claim 12, wherein the burner assemblyis a sealed burner assembly.
 21. The thermal transfer device of claim12, wherein the transfer tube has a negative pressure relative to apressure of the main chamber and the vestibule.